Structural and optical properties of low-density and In-rich InAs/GaAs quantum dots

Self-assembled InAs/GaAs quantum dots were grown at very low InAs growth rate to form sparse and large quantum dots (QDs) emitting in the near IR (1300-1400 nm), for application as single-photon sources. The structural and optical properties of these QDs as a function of the growth rate were systematically studied. The QDs grown at the lowest rate (.apprx.10-3 ML/s) present a very low dot d. (.apprx.2 * 108 dots/cm2), high In content, and good size homogeneity. Photoluminescence and time-resolved photoluminescence measurements performed at different powers and temps. provide information on their luminescence efficiency, and on the recombination processes occurring in the low-d. QDs as compared to higher densities. [on SciFinder (R)]